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Ju T, Zhang X, Jin D, Ji X, Wu P. A review of microplastics on anammox: Influences and mechanisms. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121801. [PMID: 39013314 DOI: 10.1016/j.jenvman.2024.121801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 06/11/2024] [Accepted: 07/07/2024] [Indexed: 07/18/2024]
Abstract
Microplastics (MPs) are prevalent in diverse environmental settings, posing a threat to plants and animals in the water and soil and even human health, and eventually converged in wastewater treatment plants (WWTPs), threatening the stable operation of anaerobic ammonium oxidation (anammox). Consequently, a comprehensive summary of their impacts on anammox and the underlying mechanisms must be provided. This article reviews the sources and removal efficiency of MPs in WWTPs, as well as the influencing factors and mechanisms on anammox systems. Numerous studies have demonstrated that MPs in the environment can enter WWTPs via domestic wastewater, rainwater, and industrial wastewater discharges. More than 90% of these MPs are found to accumulate in the sludge following their passage through the treatment units of the WWTPs, affecting the characteristics of the sludge and the efficiency of the microorganisms treating the wastewater. The key parameters of MPs, encompassing concentration, particle size, and type, exert a notable influence on the nitrogen removal efficiency, physicochemical characteristics of sludge, and microbial community structure in anammox systems. It is noteworthy that extracellular polymer secretion (EPS) and reactive oxygen stress (ROS) are important impact mechanisms by which MPs exposure affects anammox systems. In addition, the influence of MPs exposure on the microbial community structure of anammox cells represents a crucial mechanism that demands attention. Future research endeavors will delve into additional crucial parameters of MPs, such as shape and aging, to investigate their effects and mechanisms on anammox. Furthermore, the effective mitigation strategies will also be developed. The paper provides a fresh insight to reveal the influences of MPs exposure on the anammox process and its influence mechanisms, and lays the groundwork for further exploration into the influence of MPs on anammox and potential mitigation strategies.
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Affiliation(s)
- Ting Ju
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Xiaonong Zhang
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Da Jin
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Xu Ji
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Peng Wu
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
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2
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Johnston J, Vilardi K, Cotto I, Sudarshan A, Bian K, Klaus S, Bachmann M, Parsons M, Wilson C, Bott C, Pinto A. Metatranscriptomic Analysis Reveals Synergistic Activities of Comammox and Anammox Bacteria in Full-Scale Attached Growth Nitrogen Removal System. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:13023-13034. [PMID: 39001848 PMCID: PMC11271001 DOI: 10.1021/acs.est.4c04375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 07/09/2024] [Accepted: 07/09/2024] [Indexed: 07/15/2024]
Abstract
Leveraging comammox Nitrospira and anammox bacteria for shortcut nitrogen removal can drastically lower the carbon footprint of wastewater treatment facilities by decreasing aeration energy, carbon, alkalinity, and tank volume requirements while also potentially reducing nitrous oxide emissions. However, their co-occurrence as dominant nitrifying bacteria is rarely reported in full-scale wastewater treatment. As a result, there is a poor understanding of how operational parameters, in particular, dissolved oxygen, impact their activity and synergistic behavior. Here, we report the impact of dissolved oxygen concentration (DO = 2, 4, 6 mg/L) on the microbial community's transcriptomic expression in a full-scale integrated fixed film activated sludge (IFAS) municipal wastewater treatment facility where nitrogen removal is predominantly performed by comammox Nitrospira and anammox bacterial populations. 16S rRNA transcript compositions revealed anammox bacteria and Nitrospira were significantly more active in IFAS biofilms compared to suspended sludge biomass. In IFAS biofilms, anammox bacteria significantly increased hzo expression at lower dissolved oxygen concentrations and this increase was highly correlated with the amoA expression levels of comammox bacteria. Interestingly, the genes involved in nitrite oxidation by comammox bacteria were significantly more upregulated, relative to the genes involved in ammonia oxidation with decreasing dissolved oxygen concentrations. Ultimately, our findings suggest that comammox Nitrospira supplies anammox bacteria with nitrite via ammonia oxidation and that this synergistic behavior is dependent on dissolved oxygen concentrations.
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Affiliation(s)
- Juliet Johnston
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Katherine Vilardi
- Department
of Civil and Environmental Engineering, Northeastern University, Boston, Massachusetts 02115, United States
| | - Irmarie Cotto
- Department
of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington 98195, United States
| | - Ashwin Sudarshan
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Kaiqin Bian
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Stephanie Klaus
- Hampton
Roads Sanitation District, Virginia Beach, Virginia 23455, United States
| | - Megan Bachmann
- Hampton
Roads Sanitation District, Virginia Beach, Virginia 23455, United States
- Department
of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Mike Parsons
- Hampton
Roads Sanitation District, Virginia Beach, Virginia 23455, United States
| | - Christopher Wilson
- Hampton
Roads Sanitation District, Virginia Beach, Virginia 23455, United States
| | - Charles Bott
- Hampton
Roads Sanitation District, Virginia Beach, Virginia 23455, United States
| | - Ameet Pinto
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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3
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Wang S, Tian Y, Bi Y, Meng F, Qiu C, Yu J, Liu L, Zhao Y. Recovery strategies and mechanisms of anammox reaction following inhibition by environmental factors: A review. ENVIRONMENTAL RESEARCH 2024; 252:118824. [PMID: 38588911 DOI: 10.1016/j.envres.2024.118824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/10/2024] [Accepted: 03/27/2024] [Indexed: 04/10/2024]
Abstract
Anaerobic ammonium oxidation (anammox) is a promising biological method for treating nitrogen-rich, low-carbon wastewater. However, the application of anammox technology in actual engineering is easily limited by environmental factors. Considerable progress has been investigated in recent years in anammox restoration strategies, significantly addressing the challenge of poor reaction performance following inhibition. This review systematically outlines the strategies employed to recover anammox performance following inhibition by conventional environmental factors and emerging pollutants. Additionally, comprehensive summaries of strategies aimed at promoting anammox activity and enhancing nitrogen removal performance provide valuable insights into the current research landscape in this field. The review contributes to a comprehensive understanding of restoration strategies of anammox-based technologies.
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Affiliation(s)
- Shaopo Wang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China
| | - Yu Tian
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China
| | - Yanmeng Bi
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China
| | - Fansheng Meng
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China
| | - Chunsheng Qiu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China
| | - Jingjie Yu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China
| | - Lingjie Liu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin, 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China.
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China.
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Naufal M, Wu JH. Chemomixoautotrophy and stress adaptation of anammox bacteria: A review. WATER RESEARCH 2024; 257:121663. [PMID: 38669739 DOI: 10.1016/j.watres.2024.121663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 01/16/2024] [Accepted: 04/21/2024] [Indexed: 04/28/2024]
Abstract
Anaerobic ammonium oxidizing (anammox) bacteria, which were first discovered nearly three decades ago, are crucial for treating ammonium-containing wastewater. Studies have reported on the biochemical nitrogen conversion process and the physiological, phylogenic, and ecological features of anammox bacteria. For a long time, anammox bacteria were assumed to have a lithoautotrophic lifestyle. However, recent studies have suggested the functional versatility of anammox bacteria. Genome-based analysis and experiments with enrichment cultures have demonstrated the association of the metabolic activities of anammox bacteria with different stress conditions, revealing the importance of utilizing specific organic substances, including organoautotrophy, for growth and adaptation to stress conditions. Our understanding regarding the utilization and metabolism of organic substances and their associations with anammox reactions in anammox bacteria is growing but still incomplete. In this review, we summarize the effect of the utilization of organic substances by anammox bacteria under environmental stress conditions, emphasizing their potential organoautotrophic activity and metabolic flexibility. Although most anammox bacteria may utilize specific organic substances, Ca. Brocadia exhibited the highest level of mixoautotrophic activity. The environmental factors that substantially affect the organoautotrophic activities of anammox bacteria were also examined. This review provides a new perspective on the organoautotrophic capacity of anammox bacteria.
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Affiliation(s)
- Muhammad Naufal
- Department of Environmental Engineering, National Cheng Kung University, No.1, University Road, East District, Tainan City 70101, Taiwan
| | - Jer-Horng Wu
- Department of Environmental Engineering, National Cheng Kung University, No.1, University Road, East District, Tainan City 70101, Taiwan.
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5
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Guo H, Gao M, Yao Y, Zou X, Zhang Y, Huang W, Liu Y. Enhancing anammox process with granular activated carbon: A study on Microbial Extracellular Secretions (MESs). THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171980. [PMID: 38537814 DOI: 10.1016/j.scitotenv.2024.171980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/29/2024] [Accepted: 03/23/2024] [Indexed: 04/05/2024]
Abstract
Granular activated carbon (GAC), a porous carbon-based material, provides increased attachment space for functional microorganisms and enhances nitrogen removal by facilitating extracellular electron transfer in the anammox process. This study investigates the effects of GAC on the biosynthesis of microbial extracellular secretions (MESs) and explores the roles of these secretions in anammox activities. Four lab-scale reactors were operated: two downstream UASB reactors (D1 and D2) receiving effluents from the upstream UASB reactors (U1: no-GAC, U2: yes-GAC). Our results indicate that MESs were enhanced with the addition of GAC. The effluent from U2 exhibited a 59.62 % higher amino acid content than that from U1. These secretions contributed to an increase in the nitrogen loading rate (NLR) in the downstream reactors. Specifically, NLR in D1 increased from 130.5 to 142.7 g N/m3/day, and in D2, it escalated from 137.5 to 202.8 g N/m3/day, likely through acting as cross-feeding substrates or vital nutrients. D2 also showed increased anammox bacterial activity, enriched Ca. Brocadia population and hao gene abundance. Furthermore, this study revealed that D2 sludge has significantly higher extracellular polymeric substances (EPS) (48.71 mg/g VSS) and a larger average granule size (1.201 ± 0.119 mm) compared to D1 sludge. Overall, GAC-stimulated MESs may have contributed to the enhanced performance of the anammox process.
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Affiliation(s)
- Hengbo Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Mengjiao Gao
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Yiduo Yao
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Xin Zou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yihui Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Wendy Huang
- Department of Civil Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; School of Civil and Environmental Engineering, Queensland University of Technology, Brisbane, Queensland 4000, Australia.
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Xiong YT, Liao XW, Guo JS, Fang F, Chen YP, Yan P. Potential Role of the Anammoxosome in the Adaptation of Anammox Bacteria to Salinity Stress. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6670-6681. [PMID: 38564406 DOI: 10.1021/acs.est.4c01417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The underlying adaptative mechanisms of anammox bacteria to salt stress are still unclear. The potential role of the anammoxosome in modulating material and energy metabolism in response to salinity stress was investigated in this study. The results showed that anammox bacteria increased membrane fluidity and decreased mechanical properties by shortening the ladderane fatty acid chain length of anammoxosome in response to salinity shock, which led to the breakdown of the proton motive force driving ATP synthesis and retarded energy metabolism activity. Afterward, the fatty acid chain length and membrane properties were recovered to enhance the energy metabolic activity. The relative transmission electron microscopy (TEM) area proportion of anammoxosome decreased from 55.9 to 38.9% under salinity stress. The 3D imaging of the anammox bacteria based on Synchrotron soft X-ray tomography showed that the reduction in the relative volume proportion of the anammoxosome and the concave surfaces was induced by salinity stress, which led to the lower energy expenditure of the material transportation and provided more binding sites for enzymes. Therefore, anammox bacteria can modulate nitrogen and energy metabolism by changing the membrane properties and morphology of the anammoxosome in response to salinity stress. This study broadens the response mechanism of anammox bacteria to salinity stress.
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Affiliation(s)
- Yu-Tong Xiong
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xi-Wen Liao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Jin-Song Guo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Fang Fang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - You-Peng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Peng Yan
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
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7
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Zhang J, Xu Z, Deng X, Zhang Q, Ruan Y, Ji XM. Deciphering behaviors of 6:2 chlorinated polyfluorinated ether sulfonate (alternative-PFOS) on anammox processes: Nitrogen removal efficiency and microbial adaptability. BIORESOURCE TECHNOLOGY 2024; 397:130500. [PMID: 38423487 DOI: 10.1016/j.biortech.2024.130500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/21/2024] [Accepted: 02/25/2024] [Indexed: 03/02/2024]
Abstract
This study investigates the behaviors and effects of F-53B, an alternative to perfluorooctane sulfonate on anaerobic ammonium oxidation (anammox) processes. Results showed that the nitrogen removal efficiency (NRE) reached 83.8 % at a F-53B concentration of 0.5 mg·L-1, while NRE decreased to 66.9 % with 5 mg·L-1 of F-53B. The defluorination rates of 17.8 % (0.5 mg·L-1) and 9.3 % (5 mg·L-1) were observed, respectively, suggesting the occurrence of F-53B degradation. The relative abundance of Ca. Kuenenia decreased from 26.1 % to 16.2 % with the F-53B concentration increasing from 0.5 mg·L-1 to 5 mg·L-1. Meanwhile, Denitratisoma was selectively enriched with a relative abundance of 40.7 % at an F-53B concentration of 0.5 mg·L-1. Ca. Kuenenia could reduce reactive oxygen species induced by F-53B to maintain the balance of oxidative stress. This study gains insight into the behaviors and metabolic mechanisms of F-53B in anammox consortia, suggesting the feasibility of anammox processes for industrial wastewater.
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Affiliation(s)
- Jiaqi Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Ziyu Xu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiangqi Deng
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Quan Zhang
- School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Yang Ruan
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China; Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiao-Ming Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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8
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Qiao X, Ding L, Fang F, Fu C, Wei R, Chen Y, Zheng S, Wang X, Yan Y, Yang K, Xu N, Tao H, Yu K, Zhang L. An integrated meta-omics approach reveals the different response mechanisms of two anammox bacteria towards fluoroquinolone antibiotics. ENVIRONMENT INTERNATIONAL 2024; 185:108505. [PMID: 38394916 DOI: 10.1016/j.envint.2024.108505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/03/2024] [Accepted: 02/14/2024] [Indexed: 02/25/2024]
Abstract
The emerging fluoroquinolone antibiotics (FQs) are highly influential in nitrogen removal from livestock wastewater. However, beyond the capability of nitrogen removal, little is known about the molecular mechanisms (e.g., shift of core metabolism and energy allocation) of different anaerobic ammonium-oxidizing bacteria (AnAOB) under continuous FQ stress. This study investigated the effects of ciprofloxacin, ofloxacin and their mixture at concentrations detected in livestock wastewater on two key anammox species in membrane bioreactors. It was found 20 μg/L FQs promoted nitrogen removal efficiency and community stability, and42-51 % of FQs were removed simultaneously. Integrated meta-omics analysis revealed varied gene expression patterns between the two dominant AnAOB, Candidatus Brocadia sapporoensis (B AnAOB) and Candidatus Kuenenia stuttgartiensis (K AnAOB). The nitrogen metabolic processes were bolstered in B AnAOB, while those involved in anammox pathway of K AnAOB were inhibited. This difference was tentatively attributed to the up-regulation of reactive oxygen species scavenger genes (ccp and dxf) and FQ resistance gene (qnrB72) in B AnAOB. Importantly, most enhanced core biosynthesis/metabolism of AnAOB and close cross-feeding with accompanying bacteria were also likely to contribute to their higher levels of biomass yield and metabolism activity under FQ stress. This finding suggests that B AnAOB has the advantage of higher nitrogen metabolism capacity over K AnAOB in livestock wastewater containing FQs, which is helpful for efficient and stable nitrogen removal by the functional anammox species.
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Affiliation(s)
- Xuejiao Qiao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Lingyun Ding
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China
| | - Fang Fang
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Chenkun Fu
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ruqian Wei
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yizhen Chen
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Sihan Zheng
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xisong Wang
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yan Yan
- State Key Laboratory of Isotope Geochemistry, CAS Center for Excellence in Deep Earth Science, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510000, China
| | - Kai Yang
- China MCC5 Group Corporation Limited, Chengdu 610023, China
| | - Nan Xu
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Huchun Tao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ke Yu
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| | - Lijuan Zhang
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
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9
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Yuan M, Shan Q, Fu M, Deng M, Wang J, Deng F. Larger hydroxyapatite aggregation from Ca 2+ adhesion in ANAMMOX granular sludge caused by high dissolved oxygen. CHEMOSPHERE 2024; 350:141158. [PMID: 38199496 DOI: 10.1016/j.chemosphere.2024.141158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 12/03/2023] [Accepted: 01/07/2024] [Indexed: 01/12/2024]
Abstract
Anaerobic ammonia oxidation (ANAMMOX), a sustainable biological process, is promising to remove NH4+-N from municipal sewage. In this study, results showed that the anammox granular sludge morphology changes with the alternation of dissolved oxygen (DO), mainly attributing to the adhesion of calcium ions (Ca2+) to the surface of sludge particles. Diverse characterization methods revealed that gray adhesions in the form of hydroxyapatite covered the original holes on the anammox granular sludge surface, including scanning Electron Microscopy (SEM), digital camera images, Energy Dispersive Spectrometer (EDS), and X-ray diffraction (XRD). Ex-situ degradation of NH4+-N and NO2--N yielded diverse outcomes. The protein to polysaccharide ratio (PN/PS) in the total extracellular polymeric substances (EPS) across 4 size groups demonstrated a decrease under O2 exposure. Microbial community analysis indicated norank_f_A4b and Nitrolancea being the most abundant genus under O2 exposure at day 1 and day 100, respectively. These findings offer an effective strategy to prevent size-larger granular sludge from deteriorating through changing DO and Ca2+ in municipal wastewater in ANAMMOX.
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Affiliation(s)
- Mu Yuan
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Qiu Shan
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Mengqi Fu
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Mengxuan Deng
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jue Wang
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Fengxia Deng
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
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10
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Teng Z, Lin X. Sediment nitrates reduction processes affected by non-native Sonneratia apetala plantation in South China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167523. [PMID: 37788768 DOI: 10.1016/j.scitotenv.2023.167523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/19/2023] [Accepted: 09/29/2023] [Indexed: 10/05/2023]
Abstract
Numerous studies have highlighted the importance of nitrates (NOx-) reduction processes in estuarine and coastal ecosystems over the past decades. However, the biotic and abiotic factors sediment NOx- reduction processes in mangrove of varying ages are still not fully understood. Here, we investigated the dynamics of sediment NOx- reduction processes and associated gene abundances in mangroves of different ages (including 0-year unvegetated mudflats, 10 and 20-years Sonneratia apetala, as well as >40 years of mature native Kandelia obovate) on the Qi'ao Island using 15N stable-isotope pairing techniques and quantitative PCR. The denitrification (2.64-11.30 nmol g-1 h-1), anammox (0.06-0.83 nmol g-1 h-1), and dissimilatory nitrate reduction to ammonium (DNRA, 0.58-16.34 nmol g-1 h-1) rates varied spatially and seasonally, but their contributions to the total NOx- reduction (DEN%, ANA%, and DNRA%), associated gene abundance (nirS, anammox 16S rRNA, and nrfA), and organic matter only varied spatially. Organic matter and microbial abundances are the dominating factors controlling N loss and retention. Without considering confounding factors, mangroves conservation and restoration significantly increased DNRA rates, NIRI (DNRA/(denitrification + anammox)), organic matter content, and microbial abundances (p < 0.05 for all), but reduced N loss rates. Mangroves conservation and restoration are estimated to have increased sediment N retention (~931.81 t N yr-1) and reduced N loss (~481.32 t N yr-1) in coastal wetlands of China over the past 40 years (1980-2020). Overall, our results indicate that mangrove restoration and conservation can significantly increase sediment N retention due to the rapid biomass accumulation, and it can provide more nutrients for mangrove and microorganism growth, thus creating a virtuous cycle in these N-limited ecosystems.
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Affiliation(s)
- Zhenzhen Teng
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Xianbiao Lin
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
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11
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Wang K, Li J, Gu X, Wang H, Li X, Peng Y, Wang Y. How to Provide Nitrite Robustly for Anaerobic Ammonium Oxidation in Mainstream Nitrogen Removal. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21503-21526. [PMID: 38096379 DOI: 10.1021/acs.est.3c05600] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Innovation in decarbonizing wastewater treatment is urgent in response to global climate change. The practical implementation of anaerobic ammonium oxidation (anammox) treating domestic wastewater is the key to reconciling carbon-neutral management of wastewater treatment with sustainable development. Nitrite availability is the prerequisite of the anammox reaction, but how to achieve robust nitrite supply and accumulation for mainstream systems remains elusive. This work presents a state-of-the-art review on the recent advances in nitrite supply for mainstream anammox, paying special attention to available pathways (forward-going (from ammonium to nitrite) and backward-going (from nitrate to nitrite)), key controlling strategies, and physiological and ecological characteristics of functional microorganisms involved in nitrite supply. First, we comprehensively assessed the mainstream nitrite-oxidizing bacteria control methods, outlining that these technologies are transitioning to technologies possessing multiple selective pressures (such as intermittent aeration and membrane-aerated biological reactor), integrating side stream treatment (such as free ammonia/free nitrous acid suppression in recirculated sludge treatment), and maintaining high activity of ammonia-oxidizing bacteria and anammox bacteria for competing oxygen and nitrite with nitrite-oxidizing bacteria. We then highlight emerging strategies of nitrite supply, including the nitrite production driven by novel ammonia-oxidizing microbes (ammonia-oxidizing archaea and complete ammonia oxidation bacteria) and nitrate reduction pathways (partial denitrification and nitrate-dependent anaerobic methane oxidation). The resources requirement of different mainstream nitrite supply pathways is analyzed, and a hybrid nitrite supply pathway by combining partial nitrification and nitrate reduction is encouraged. Moreover, data-driven modeling of a mainstream nitrite supply process as well as proactive microbiome management is proposed in the hope of achieving mainstream nitrite supply in practical application. Finally, the existing challenges and further perspectives are highlighted, i.e., investigation of nitrite-supplying bacteria, the scaling-up of hybrid nitrite supply technologies from laboratory to practical implementation under real conditions, and the data-driven management for the stable performance of mainstream nitrite supply. The fundamental insights in this review aim to inspire and advance our understanding about how to provide nitrite robustly for mainstream anammox and shed light on important obstacles warranting further settlement.
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Affiliation(s)
- Kaichong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai 200092, P. R. China
| | - Jia Li
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai 200092, P. R. China
| | - Xin Gu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai 200092, P. R. China
| | - Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai 200092, P. R. China
| | - Xiang Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, P. R. China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, P. R. China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai 200092, P. R. China
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12
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Liu J, Ran X, Li J, Wang H, Xue G, Wang Y. Novel insights into carbon nanomaterials enhancing anammox for nitrogen removal: Effects and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167146. [PMID: 37726079 DOI: 10.1016/j.scitotenv.2023.167146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/12/2023] [Accepted: 09/14/2023] [Indexed: 09/21/2023]
Abstract
Carbon nanomaterials (CNMs) possess the properties including large specific surface area, high porosity, and stable chemical structures, presenting significant application advantages in wastewater treatment. Indeed, CNMs are considered to be added to anammox systems to strengthen anammox function, especially to resolve the challenge of anammox technology, i.e., the slow growth rate of anammox bacteria, as well as its high environmental sensitivity. This paper systematically reviews the promotion effects and mechanisms of CNMs on the nitrogen removal performance of anammox system. Among the zero-, one-, and two-dimensional CNMs, two-dimensional CNMs have best promoting effect on the nitrogen removal performance of anammox system due to its excellent conductivity and abundant functional groups. Then, the promotion effects of CNMs on anammox process are summarized from the perspective of anammox activity and bacteria abundance. Furthermore, CNMs not only enhance the anammox process, but also stimulate the coupling of denitrification pathways with anammox, as well as the improvement of system operational stability (alleviating the inhibitions of low temperature and pH fluctuation), thus contributing to the promoted nitrogen removal performance. Essentially, CNMs are capable of facilitating microbial immobilization and electron transfer, which favor to improve the efficiency and stability of anammox process. Finally, this review highlights the gap in knowledge and future work, aiming to provide a deeper understanding of how CNMs can strengthen the anammox system and provide a novel perspective for the engineering of the anammox process.
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Affiliation(s)
- Jiawei Liu
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Xiaochuan Ran
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Jia Li
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China.
| | - Gang Xue
- Shanghai Institute of Pollution Control and Ecological Security, Donghua University, Shanghai 201620, China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
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Yang L, Li W, Zhu H, Dong S, Mu H, Hu K, Wang T, Li J. Functions and mechanisms of sponge iron-mediated multiple metabolic processes in anaerobic ammonium oxidation. BIORESOURCE TECHNOLOGY 2023; 390:129821. [PMID: 37806360 DOI: 10.1016/j.biortech.2023.129821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/10/2023]
Abstract
Sponge iron (SI) is a promising material for nitrogen removal from wastewater. This study reveals the potential functions and mechanisms of SI-mediated multiple metabolic processes in the nitrogen removal of Anammox. The results showed that although the SI application prolonged the start-up time of the reactor, achieved efficient and stable nitrogen removal after a successful start-up. The total nitrogen removal efficiency of the SI-Anammox system (92.62%) was 13.30% higher than that of R0 without SI (79.32%). The increase in nitrogen removal performance was accompanied by an increase in SAA and EPS content. Further microbial analysis showed significant enrichment of functional microorganisms, such as Candidatus_Brocadia, Nitrosomonas, Ellin6067, and Nitrospira. Multi-omics evidence suggests that efficient nitrogen removal is ultimately attributable to the enhancement of the specific key Fe- and N-functional genes in Anammox.
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Affiliation(s)
- Lili Yang
- College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Wenxuan Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; State Environmental Protection Key Laboratory of Ecological Effect and Risk Assessment of Chemicals, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Hongjuan Zhu
- College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Sanqiang Dong
- College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Hao Mu
- College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Kaiyao Hu
- College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Te Wang
- Shaanxi Municipal Architectural Design & Research Institute Co., Ltd., Xi'an 710000, China
| | - Jie Li
- College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China; Key Laboratory of Yellow River Water Environment in Gansu Province, Lanzhou 730070, China; Key Laboratory for Resources Utilization Technology of Unconventional Water of Gansu Province, Lanzhou 730020, China
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14
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Zhang L, Dong T, Yang J, Hao S, Sun Z, Peng Y. Anammox Coupled with Photocatalyst for Enhanced Nitrogen Removal and the Activated Aerobic Respiration of Anammox Bacteria Based on cbb3-Type Cytochrome c Oxidase. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17910-17919. [PMID: 37463493 DOI: 10.1021/acs.est.3c02435] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
This study introduced photogenerated electrons into the anammox system by coupling them to a g-C3N4 nanoparticle photocatalyst. A high nitrogen removal efficiency (94.25%) was achieved, exceeding the biochemical limit of 89% imposed by anammox stoichiometry. Photogenerated electrons boosted anammox metabolic activity by empowering key enzymes (NIR, HZS, and WLP-related proteins) and triggered rapid algal enrichment by enhancing the algal Calvin cycle, thus developing multiple anammox-algae synergistic nitrogen removal processes. Remarkably, the homologous expression of cbb3-type cytochrome c oxidase (CcO) in anammox bacteria was discovered and reported in this study for the first time. This conferred aerobic respiration capability to anammox bacteria and rendered them the principal oxygen consumer under 7.9-19.8 mg/L dissolved oxygen, originating from algal photosynthesis. Additionally, photogenerated electrons selectively targeted the cb1 complex and cbb3-type CcO as activation sites while mobilizing the RegA/B regulatory system to activate the expression of cbb3-type CcO. Furthermore, cbb3-type CcO blocked oxidative stress in anammox by depleting intracellular oxygen, a substrate for reactive oxygen species synthesis. This optimized the environmental sensitivity of anammox bacteria and maintained their high metabolic activity. This study expands our understanding of the physiological aptitudes of anammox bacteria and provides valuable insights into applying solar energy for enhanced wastewater treatment.
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Affiliation(s)
- Li Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing 100124, China
| | - Tingjun Dong
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing 100124, China
| | - Jiachun Yang
- Shuifa Shandong Water Development Group Co. Ltd., Shandong 274200, China
- Shandong Jianzhu University, Shandong 250101, China
| | - Shiwei Hao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing 100124, China
| | - Zaicheng Sun
- Center of Excellence for Environmental Safety and Biological Effects, Beijing Key Laboratory for Green Catalysis and Separation, Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing 100124, China
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15
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Su Y, Du R, Wang J, Li X, Zhang Q, Xue X, Peng Y. Pilot-scale demonstration of self-enrichment of anammox bacteria in a two-stage nitrification-denitrification suspended sludge system treating municipal wastewater under extremely low nitrogen loading rate. BIORESOURCE TECHNOLOGY 2023; 387:129693. [PMID: 37598806 DOI: 10.1016/j.biortech.2023.129693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/13/2023] [Accepted: 08/17/2023] [Indexed: 08/22/2023]
Abstract
In suspended sludge system, efficient enrichment and retention of anammox bacteria are crucial obstacles in mainstream wastewater treatment by anammox process. In this study, anammox bacteria was self-enriched in a pilot-scale suspended sludge system of two-stage nitrification-denitrification process serving municipal wastewater treatment. With the low ammonia (NH4+-N) of 9.3 mg/L, nitrate (NO3--N) of 15.6 mg/L and COD/NO3--N of 2.2 under extremely low nitrogen loading rate of 0.012 kg N/m3/d, anammox activity bloomed after its abundance increasing from 5.9 × 107 to 4.6 × 109 copies/g dry sludge. Significant NH4+-N removal was occurred and maintained stably in the denitrification reactor with anammox bacteria accounting for 1.13%, even under temperature decreasing to 20.0℃. The adequately anoxic environment, efficient retention with the static settlement, and NO2- production via NO3- reduction provided favorable environment for anammox bacteria. This study demonstrated the feasibility and great potential in mainstream anammox application without seeding specific sludge.
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Affiliation(s)
- Yunlong Su
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Rui Du
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| | - Jiao Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiaofei Xue
- Beijing Enterprises Water Group (China) Investment Limited, Beijing 100102, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
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16
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Liu L, Pan Y, Zhi X, Chen L, Zhu H. Bacterial antioxidant mechanism in calcium peroxide aided sludge anaerobic fermentation. BIORESOURCE TECHNOLOGY 2023; 384:129327. [PMID: 37328013 DOI: 10.1016/j.biortech.2023.129327] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/13/2023] [Accepted: 06/11/2023] [Indexed: 06/18/2023]
Abstract
Although calcium peroxide (CaO2) can enhance the short-chain fatty acids (SCFAs) production in sludge anaerobic fermentation, the microbiological mechanisms underlying this process remain unclear. In this study, it is aimed to elucidate the bacterial protective mechanisms in response to the oxidative stress induced by CaO2. Results show that extracellular polymeric substance (EPS) and anti-oxidant enzymes play vital roles in protecting bacterial cells from CaO2. The addition of CaO2 resulted in increased relative abundances of genes exoP and SRP54, which are associated with EPS secretion and transportation. Superoxide dismutase (SOD) played a crucial in alleviating oxidative stress. The dosage of CaO2 significantly influences the succession of the bacterial community in the anaerobic fermentation system. With 0.3 g CaO2/g VSS, the net income was approximately 4 USD/ton of sludge treated. The CaO2-assisted anaerobic fermentation process has the potential to recover more resources from sludge and thus, benefit the environment.
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Affiliation(s)
- Li Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Yu Pan
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Xiaohan Zhi
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Long Chen
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Hongtao Zhu
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
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17
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Kong L, Zheng R, Feng Y, Du W, Xie C, Gu Y, Liu S. Anammox bacteria adapt to long-term light irradiation in photogranules. WATER RESEARCH 2023; 241:120144. [PMID: 37300965 DOI: 10.1016/j.watres.2023.120144] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/13/2023] [Accepted: 05/28/2023] [Indexed: 06/12/2023]
Abstract
Photogranules composed of algae, nitrifiers, and anammox bacteria are promising for nitrogen removal from wastewater with reduced aeration and carbon emissions. However, it is difficult to be achieved as the potential inhibition of anammox bacteria by light. In this study, a syntrophic algal-partial nitrification/anammox granular sludge process was developed, with a nitrogen removal rate of 294.5 mg N/(L·d). We found the symbiosis in the community promoted the adaptation of anammox bacteria under light, and cross-feeding played an important role. Microalgae in the outer layers of photogranules sheltered most of the light and supplied cofactors and amino acids to promote nitrogen removal. In particular, Myxococcota MYX1 degraded the extracellular proteins produced by microalgae, providing amino acids to the entire bacterial community, which helped anammox bacteria save metabolic energy and adapt to light. Notably, the anammox bacteria Candidatus Brocadia exhibited unique light-sensing potential and adaptations to light irradiation compared with Candidatus Jettenia, including diverse DNA repair, scavenging of reactive oxygen species, cell movement. The phytochrome-like proteins encoded by Candidatus Brocadia further facilitated their spatial positioning and niche partitioning in photogranules. This study provides insights into the response of anammox bacteria in the algae-bacteria symbiosis system and suggests its potential application for carbon-negative nitrogen removal.
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Affiliation(s)
- Lingrui Kong
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Ru Zheng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Yiming Feng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Wenran Du
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Chen Xie
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Yuanqi Gu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Sitong Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China.
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18
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Pan J, Zhou J, Tang X, Guo Y, Zhao Y, Liu S. Bacterial Communication Coordinated Behaviors of Whole Communities to Cope with Environmental Changes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4253-4265. [PMID: 36862939 DOI: 10.1021/acs.est.2c05780] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Bacterial communication plays an important role in coordinating microbial behaviors in a community. However, how bacterial communication organizes the entire community for anaerobes to cope with varied anaerobic-aerobic conditions remains unclear. We constructed a local bacterial communication gene (BCG) database comprising 19 BCG subtypes and 20279 protein sequences. BCGs in anammox-partial nitrification consortia coping with intermittent aerobic and anaerobic conditions as well as gene expressions of 19 species were inspected. We found that when suffering oxygen changes, intra- and interspecific communication by a diffusible signal factor (DSF) and bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) changed first, which in turn induced changes of autoinducer-2 (AI-2)-based interspecific and acyl homoserine lactone (AHLs)-based intraspecific communication. DSF and c-di-GMP-based communication regulated 455 genes, which covered 13.64% of the genomes and were mainly involved in antioxidation and metabolite residue degradation. For anammox bacteria, oxygen influenced DSF and c-di-GMP-based communication through RpfR to upregulate antioxidant proteins, oxidative damage-repairing proteins, peptidases, and carbohydrate-active enzymes, which benefited their adaptation to oxygen changes. Meanwhile, other bacteria also enhanced DSF and c-di-GMP-based communication by synthesizing DSF, which helped anammox bacteria survive at aerobic conditions. This study evidences the role of bacterial communication as an "organizer" within consortia to cope with environmental changes and sheds light on understanding bacterial behaviors from the perspective of sociomicrobiology.
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Affiliation(s)
- Juejun Pan
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Jianhang Zhou
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Xi Tang
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yongzhao Guo
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yunpeng Zhao
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Sitong Liu
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
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Zhang Q, Zheng J, Zhao L, Liu W, Chen L, Cai T, Ji XM. Succession of microbial communities reveals the inevitability of anammox core in the development of anammox processes. BIORESOURCE TECHNOLOGY 2023; 371:128645. [PMID: 36681349 DOI: 10.1016/j.biortech.2023.128645] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/09/2023] [Accepted: 01/15/2023] [Indexed: 06/17/2023]
Abstract
The lack of anammox seeds is regarded as the bottleneck of anammox-based processes. Although the interactions in anammox consortia have attracted increasing attention, little is known about the influence of inoculated sludge populations on the growth of anammox bacteria. In this study, four sludge of distinct communities mixed with anammox sludge (the relative abundance of Ca. Kuenenia was 1.96 %) were used as the seeds, respectively for the start-up of anammox processes. Notably, all these mixed microbial communities tend to form a similar microbial community, defined as the anammox core, containing anammox-bacteria (22.9 ± 5.9 %), ammonia-oxidizing-bacteria (0.8 ± 0.7 %), nitrite-oxidizing-bacteria (0.2 ± 0.2 %), Chloroflexi-bacteria (0.7 ± 0.4 %), and heterotrophic-denitrification-bacteria (0.3 ± 0.2 %). It also elucidated that the communities of Nitrosomonas-dominated sludge were the closest to the anammox core, and achieved the highest nitrogen-removal rate of 0.73 kg-N m-3 d-1. This study sheds light on the solution to the shortage of anammox seeds in the full-scale wastewater treatment application.
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Affiliation(s)
- Qi Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jinli Zheng
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Leizhen Zhao
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Wenru Liu
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Liwei Chen
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Tianming Cai
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiao-Ming Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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Shao YH, Wu YW, Naufal M, Wu JH. Genome-centered metagenomics illuminates adaptations of core members to a partial Nitritation-Anammox bioreactor under periodic microaeration. Front Microbiol 2023; 14:1046769. [PMID: 36778888 PMCID: PMC9909701 DOI: 10.3389/fmicb.2023.1046769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 01/06/2023] [Indexed: 01/27/2023] Open
Abstract
The partial nitritation-anaerobic ammonium oxidation (anammox; PN-A) process has been considered a sustainable method for wastewater ammonium removal, with recent attempts to treat low-strength wastewater. However, how microbes adapt to the alternate microaerobic-anoxic operation of the process when treating low ammonium concentrations remains poorly understood. In this study, we applied a metagenomic approach to determine the genomic contents of core members in a PN-A reactor treating inorganic ammonium wastewater at loading as low as 0.0192 kg-N/m3/day. The metabolic traits of metagenome-assembled genomes from 18 core species were analyzed. Taxonomically diverse ammonia oxidizers, including two Nitrosomonas species, a comammox Nitrospira species, a novel Chloroflexota-related species, and two anammox bacteria, Ca. Brocadia and Ca. Jettenia, accounted for the PN-A reactions. The characteristics of a series of genes encoding class II ribonucleotide reductase, high-affinity bd-type terminal oxidase, and diverse antioxidant enzymes revealed that comammox Nitrospira has a superior adaptation ability over the competitors, which may confer the privileged partnership with anammox bacteria in the PN-A reactor. This finding is supported by the long-term monitoring experiment, showing the predominance of the comammox Nitrospira in the ammonia-oxidizing community. Metagenomic analysis of seven heterotrophs suggested that nitrate reduction is a common capability in potentially using endogenous carbohydrates and peptides to enhance nitrogen removals. The prevalence of class II ribonucleotide reductase and antioxidant enzymes genes may grant the adaptation to cyclically microaerobic/anoxic environments. The predominant heterotroph is affiliated with Chloroflexota; its genome encodes complete pathways for synthesizing vitamin B6 and methionine. By contrast, other than the two growth factors, Nitrospira and anammox bacteria are complementary to produce various vitamins and amino acids. Besides, the novel Chloroflexota-related ammonia oxidizer lacks corresponding genes for detoxifying the reactive oxygen species and thus requires the aid of co-existing members to alleviate oxidative stress. The analysis results forecast the exchanges of substrates and nutrients as well as the collective alleviation of oxidative stress among the core populations. The new findings of the genomic features and predicted microbial interplay shed light on microbial adaptation to intermittent microaeration specific to the PN-A reactor, which may aid in improving its application to low-strength ammonium wastewater.
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Affiliation(s)
- Yung-Hsien Shao
- Department of Environmental Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Wei Wu
- College of Medical Science and Technology, Graduate Institute of Biomedical Informatics, Taipei Medical University, Taipei, Taiwan
| | - Muhammad Naufal
- Department of Environmental Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Jer-Horng Wu
- Department of Environmental Engineering, National Cheng Kung University, Tainan, Taiwan,*Correspondence: Jer-Horng Wu, ✉
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21
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Shen Y. The roads taken and not taken: Trends of anammox-based wastewater treatment in China. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 13:100221. [PMID: 36471881 PMCID: PMC9718951 DOI: 10.1016/j.ese.2022.100221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
•Grants supporting anammox for wastewater treatment in China was analyzed.•The next frontiers of anammox research are prospected.•Anammox-based biotechnologies potentially drives innovation in water sector.
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22
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Yang JH, Huang DQ, Geng YC, Ling YR, Fan NS, Jin RC. Role of quorum sensing-based regulation in development of anaerobic ammonium oxidation process. BIORESOURCE TECHNOLOGY 2023; 367:128228. [PMID: 36332868 DOI: 10.1016/j.biortech.2022.128228] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
Shortage of anaerobic ammonium oxidation (anammox) sludge greatly limits the extensive full-scale application of anammox-based processes. Although numerous start-up strategies have been proposed, the interaction among microbial consortia and corresponding mechanism during the process development remain unknown. In this study, three reactors were established based on different seed sludges. After 27 days, the anammox process inoculated with anammox granules and activated sludge (1:5) was firstly achieved, and the highest nitrogen removal rate was 1.17 kg N m-3 d-1. Correspondingly, the anammox activity and abundances of related functional genes increased. Notably, the dominant anammox bacteria shifted from Candidatus Kuenenia to Candidatus Brocadia. Metagenomic analysis indicated that quorum sensing-based regulation mainly contributed to the proliferation and accumulation of anammox bacteria. This work provides an insight into the quorum sensing (QS)-regulated microbial interactions in the anammox and activated sludge consortia during the process development.
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Affiliation(s)
- Jun-Hui Yang
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Dong-Qi Huang
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Yin-Ce Geng
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Yi-Rong Ling
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Nian-Si Fan
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China; School of Engineering, Hangzhou Normal University, Hangzhou 310018, China.
| | - Ren-Cun Jin
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China; School of Engineering, Hangzhou Normal University, Hangzhou 310018, China
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23
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Ni L, Wang K, Wang Z, Wang Y. Antibiofouling Characteristics and Mechanisms in an Anammox Membrane Bioreactor Based on an Optimized Photocatalytic Technology─Photocatalytic Optical Fibers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:16144-16155. [PMID: 36269937 DOI: 10.1021/acs.est.2c04023] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
As an ecofriendly photocatalytic antifouling technology for membrane bioreactors (MBRs), photocatalytic optical fibers (POFs) can decrease the replacement cost of modified membranes and prevent the proliferation of photosynthetic bacteria caused by direct light illumination. Here, POFs were applied in situ in an anaerobic ammonium oxidation (anammox) MBR for membrane biofouling control. Compared with the control MBR without POFs treatment, the average fouling cycle of the POFs-loaded MBR was extended by 137%, and the energy consumption caused by membrane fouling was saved by 18%. In the antibiofouling process, •OH was the key photocatalytic reactive species. On the fouled POFs-loaded membranes, the membrane-adhered foulant was significantly decreased by photocatalytic degradation of the proteins, polysaccharides and humic substances in the microbial metabolites. The membrane-attached bacteria were inactivated by the POFs by the mechanisms of cell-membrane destruction and cell-membrane permeabilization, which caused bacterial necrosis and apoptosis, respectively. Moreover, the total nitrogen-removal efficiencies of the two MBRs were maintained at 85.3-90.4%, and the abundance of anammox bacteria increased from 21.3% to 46.2% during the 202 days of operation, indicating an efficient anammox process with excellent nitrogen-removal performance, biomass retention, and anammox bacteria enrichment. The systematic insights into the antibiofouling performance and mechanisms of POFs in anammox MBRs will promote application and development of membrane-filtration technology in wastewater treatment using environmentally friendly and energy-efficient antifouling strategies.
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Affiliation(s)
- Lingfeng Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
| | - Kaichong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
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24
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Zhu Z, Qin J, Chen Z, Chen Y, Chen H, Wang X. Sulfammox forwarding thiosulfate-driven denitrification and anammox process for nitrogen removal. ENVIRONMENTAL RESEARCH 2022; 214:113904. [PMID: 35863443 DOI: 10.1016/j.envres.2022.113904] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 07/04/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
The coupled process of thiosulfate-driven denitrification (NO3-→NO2-) and Anammox (TDDA) was a promising process for the treatment of wastewater containing NH4+-N and NO3--N. However, the high concentration of SO42- production limited its application, which needs to be alleviated by an economical and effective way to promote the application of TDDA process. In this study, TDDA process was started in a relatively short time by stepwise replacing nitrite with nitrate and operated continuously for 146 days. Results presented that the average total nitrogen removal efficiency of 82.18% can be acquired at a high loading rate of 1.98 kg N/(m3·d) with maximum nitrogen removal efficiency up to 87.04%. It was observed that the increase of S/N ratio improved the denitrification efficiency and slightly inhibit the Anammox process. Batch tests showed that Sulfammox process appeared in TDDA process under certain conditions, further contributing 2.59% nitrogen removal and 10.46% sulfur removal (14.42 mg/L NH4+-N and 37.68 mg/L SO42--S were removed). This finding was mainly attributed to the reduction of sulfate in TDDA system to elemental S0 or HS-, which subsequently was used as an electron donor to realize the recycling of sulfate (SO42--S) pollutants and promote the sulfur-nitrogen (S-N) cycle. High-throughput analysis displayed that Anammox bacteria (Candidatus_Kuenenia), Sulfur-oxidizing bacteria (Thiobacillus) with relatively high abundance of 5.37%, 7.74%, respectively, guaranteeing the excellent nitrogen and sulfate removal performance in the reactor. The enrichment of phyla Chloroflexi (31.79%), Proteobacteria (31.82%), class Ignavibacteriales (10.55%), genus Planctomycetes (13.57%) further verified the exitence of Sulfammox process in the TDDA reactor. This study provides a new perspective for the practical application of TDDA in terms of reducing the production of high concentration SO42- and saving operational cost and strengthening deeply nitrogen removal.
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Affiliation(s)
- Zijian Zhu
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Jiafu Qin
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Zhenguo Chen
- School of Environment, South China Normal University, Guangzhou, 510006, China; Hua An Biotech Co., Ltd., Foshan, 528300, China
| | - Yongxing Chen
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Haochuan Chen
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Xiaojun Wang
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China; Hua An Biotech Co., Ltd., Foshan, 528300, China.
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25
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Liu W, Li T, Wang J, Shen Y, Ji X, Yang D. A new concept of waste iron recycling for the enhancement of the anammox process. CHEMOSPHERE 2022; 307:136151. [PMID: 36028122 DOI: 10.1016/j.chemosphere.2022.136151] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 08/10/2022] [Accepted: 08/18/2022] [Indexed: 06/15/2023]
Abstract
As a by-product of industry, waste iron scraps (WIS) are low-cost and widely available, which was potential for the development of iron-assisted anammox. In this study, the feasibility of adding WIS to enhance the nitrogen removal of the anammox process (also called WIS-assisted anammox) was demonstrated. Results indicated that the WIS-assisted anammox reactors performed a 15-35% higher nitrogen removal efficiency than that of the control. Compared to the sludge from the control, the sludge from the WIS-assisted anammox reactors had a higher iron content (78-113 g kg-1 SS) and a better specific anammox activity (10.8-15.5 mg N g-1 VSS h-1). The enhanced growth of the anammox bacteria (related to Ca. Kuenenia stuttgartiensis with 99% similarity) in the WIS-assisted anammox reactors was also confirmed by high-throughput sequencing and qPCR. Furthermore, the functional genes predicted by PICRUSt2 revealed a higher level of hydroxylamine oxidoreductase (hao)-like proteins expression of the biomass from the WIS-assisted anammox reactors, implying that the hydroxylamine-related anammox pathway was promoted. Additionally, the observation of cytoplasmic nitrate reductase (narG), copper-containing nitrite reductase (nirK), and nitric oxide reductase (norB) suggested that the introduction of WIS might promote the denitrification ability. This was correlated to the lower ΔNO3-/ΔNH4+ ratio observed in these WIS-assisted anammox reactors. Overall, the WIS-assisted anammox offers a sustainable nitrogen removal process for wastewater treatment with waste iron recycling.
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Affiliation(s)
- Wenru Liu
- National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
| | - Tianhao Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Jianfang Wang
- National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Yaoliang Shen
- National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Xiaoming Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Dianhai Yang
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, China
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26
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Li D, Zhang J, Cheng C, Hou K, Wang X, Zhu L, Li B, Du Z, Wang J, Wang J. Effects of ecotoxicity of penoxsulam single and co-exposure with AgNPs on Eisenia fetida. CHEMOSPHERE 2022; 307:136134. [PMID: 36028129 DOI: 10.1016/j.chemosphere.2022.136134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
Penoxsulam (PNX) and silver nanoparticles (AgNPs) are likely to coexist in soils due to continuous use. However, the ecotoxicity of PNX in earthworms and the effect of AgNPs on PNX toxicity are unknown. Therefore, the toxicity of PNX (0.05, 0.5, and 2.5 mg/kg) single and co-exposure with AgNPs (10 mg/kg) after 28 and 56 days on Eisenia fetida (E. fetida) was investigated from biochemical, genetic, histopathological, and transcriptomic aspects. The results showed that the low concentration of PNX (0.05PNX) had almost no effect on the biochemical level of E. fetida. However, the addition of AgNPs resulted in 0.05PNX causing E. fetida to produce excessive reactive oxygen species, and the activity of antioxidant and detoxification enzymes were interfered, resulting in lipid peroxidation and DNA damage. From the genetic level, even the lowest concentration of PNX can significantly interfere with the expression of functional genes, thus inducing oxidative stress and apoptosis and inhibited reproductive behavior in E. fetida. The integrated biomarker response results at the biochemical and genetic levels showed that the comprehensive toxicity of PNX and PNX + AgNPs on E. fetida was PNX dose-dependent. And the toxicity of all co-exposure groups was greater than that of the PNX only exposure groups. Furthermore, the addition of AgNPs significantly increased the damage of PNX on E. fetida intestinal tissue. Meanwhile, transcriptomic analysis showed that PNX + AgNPs had a greater effect on E. fetida than PNX single, and multiple pathways related to oxidative stress, inflammation, and cellular process regulation were disturbed. These results provide a basis for comprehensive evaluation of the ecotoxicity of PNX and confirm that the AgNPs does increase the ecotoxicity of PNX in soil environment.
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Affiliation(s)
- Dengtan Li
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Jingwen Zhang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Chao Cheng
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Kaixuan Hou
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Xiaole Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Lusheng Zhu
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Bing Li
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Zhongkun Du
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Jinhua Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
| | - Jun Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian, 271018, China.
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27
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Yeap CSY, Nguyen NHA, Spanek R, Too CC, Benes V, Provaznik J, Cernik M, Sevcu A. Dissolved iron released from nanoscale zero-valent iron (nZVI) activates the defense system in bacterium Pseudomonas putida, leading to high tolerance to oxidative stress. JOURNAL OF HAZARDOUS MATERIALS 2022; 439:129627. [PMID: 35872458 DOI: 10.1016/j.jhazmat.2022.129627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 07/03/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Nanoscale zero-valent iron (nZVI) has increasingly been applied to remediate aquifers polluted by organochlorines or heavy metals. As a result, bacteria in the vicinity of remediate action can be stressed by surplus iron released from nZVI. However, the understanding of the iron stress defense pathways during this process is currently incomplete. Therefore, we aimed to elucidate the physiological and transcriptomic response of the bacterium, Pseudomonas putida NCTC 10936, to 100 mg/L of nZVI and 44.5 µg/L of dissolved iron obtained from nZVI suspension. Cell viability was neither affected by nZVI nor dissolved iron, although the dissolved iron caused stress that altered the cell physiology and caused the generation of smaller cells, whereas cells were elongated in the presence of nZVI. Transcriptomic analysis confirmed the observed stronger physiological effect caused by dissolved iron (in total 3839 differentially expressed genes [DEGs]) than by nZVI (945 DEGs). Dissolved iron (but not nZVI) activated genes involved in oxidative stress-related pathways, antioxidant activity, carbohydrate and energy metabolism, but downregulated genes associated with flagellar assembly proteins and two-component systems involved in sensing external stimuli. As a result, bacteria very effectively faced oxidative insults and cell viability was not affected.
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Affiliation(s)
- Cheryl S Y Yeap
- Institute for Nanomaterials Advanced Technologies and Innovation, Technical University of Liberec, Bendlova 1409/7, 46117 Liberec 1, Czechia; Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 2, 461 17 Liberec 1, Czechia
| | - Nhung H A Nguyen
- Institute for Nanomaterials Advanced Technologies and Innovation, Technical University of Liberec, Bendlova 1409/7, 46117 Liberec 1, Czechia
| | - Roman Spanek
- Institute for Nanomaterials Advanced Technologies and Innovation, Technical University of Liberec, Bendlova 1409/7, 46117 Liberec 1, Czechia; Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 2, 461 17 Liberec 1, Czechia
| | - Chin Chin Too
- Department of Biochemistry and Microbiology, Ghent University, K. L. Ledeganckstraat 35, Campus Ledeganck, 9000 Ghent, Belgium
| | - Vladimir Benes
- Genomics Core Facility, European Molecular Biology Laboratory of Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Jan Provaznik
- Genomics Core Facility, European Molecular Biology Laboratory of Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Miroslav Cernik
- Institute for Nanomaterials Advanced Technologies and Innovation, Technical University of Liberec, Bendlova 1409/7, 46117 Liberec 1, Czechia
| | - Alena Sevcu
- Institute for Nanomaterials Advanced Technologies and Innovation, Technical University of Liberec, Bendlova 1409/7, 46117 Liberec 1, Czechia; Faculty of Science, Humanities and Education, Technical University of Liberec, Studentská 2, 461 17 Liberec 1, Czechia.
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28
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Li J, Peng Y, Yang S, Li S, Feng W, Li X, Zhang Q, Zhang L. Successful Application of Anammox Using the Hybrid Autotrophic-Heterotrophic Denitrification Process for Low-Strength Wastewater Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:13964-13974. [PMID: 36000687 DOI: 10.1021/acs.est.2c02920] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Directly integrating anammox into sewage treatment is attractive, but anammox bacteria (AnAOB) enrichment is complex due to vicious competition from heterotrophic bacteria (HB). A novel strategy of optimal organics management using a preanaerobic stage and subsequent limited-oxygen conditions (0.32 ± 0.15 mg-O2/L) is applied, and a hybrid autotrophic-heterotrophic denitrification process is developed to treat sewage-like wastewater with a COD/N ratio of 3.1 for 420 days. The stable process was achieved, and a high total nitrogen removal rate of 0.53 kg-N/(m3·d) was obtained compared to conventional nitrification/denitrification. The 16S rRNA high-throughput sequencing analysis suggested that the relative abundance of the nonendogenous HB (Denitratisoma and Thauera) was drastically reduced (P ≤ 0.001), whereas the endogenous denitrifying HB (Candidatus (Ca.) Competibacter) was significantly enriched in the anammox granules (9.98%, P ≤ 0.001). Moreover, Ca. Competibacter as an inner core and Nitrospira and Ca. Brocadia as an outside coating of the anammox granules indicated the cooperation of AnAOB with HB as revealed by laser-scanning confocal microscopy and qPCR. In situ tests further confirmed nitrite from two pathways (partial nitritation and endogenous partial denitritation) that favored AnAOB enrichment. Optimal organics management can mitigate the competition of HB with AnAOB by redirecting the metabolic pathways and microbial community, which is critical to directly integrating anammox into sewage treatment.
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Affiliation(s)
- Jialin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Shenhua Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Shuai Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Wanyi Feng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
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29
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Tan X, Nie WB, Xie GJ, Dang CC, Wang XW, Xing D, Liu BF, Ding J, Ren N. Deciphering the Inhibition of Ethane on Anaerobic Ammonium Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:13419-13427. [PMID: 35917334 DOI: 10.1021/acs.est.2c01527] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Anaerobic ammonium oxidation (anammox) and nitrification, two common biological ammonium oxidation pathways, are critical for the microbial nitrogen cycle. Short chain alkanes (C2-C8) have been well-known as inhibitors for nitrification through interaction with the ammonia monooxygenase, while whether these alkanes affect anammox is an open question. Here, this work demonstrated significant inhibition of ethane on anammox and revealed the inhibitory mechanism. The acute inhibition of ethane on anammox was concentration-dependent and reversible; 0.86 mM dissolved ethane caused 50% inhibition (IC50), and 1.72 mM ethane almost completely inhibited anammox. After long-term exposure to 0.09 mM ethane for 30 days, the ammonium (nitrite) removal rate dropped from 202 (267) mg N L-1 d-1 to 1 (1) mg N L-1 d-1, and the abundance of anammox bacteria decreased from 61.9% to 9.5%. The intercellular ammonium concentration of anammox bacteria decreased after ethane exposure, while metatranscriptome analysis showed significant upregulation of genes for ammonium transport of anammox bacteria. Thus, ethane could suppress ammonium uptake resulting in the inhibition of anammox activities. As ethane is the second most prevalent alkane after methane in various anoxic environments, ethane may have an important effect on the nitrogen cycle driven by anammox that should be investigated in future research.
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Affiliation(s)
- Xin Tan
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wen-Bo Nie
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Guo-Jun Xie
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Cheng-Cheng Dang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xiao-Wei Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Bing-Feng Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jie Ding
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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Zhao Q, Guo W, Luo H, Wang H, Yu T, Liu B, Si Q, Ren N. Dissecting the roles of conductive materials in attenuating antibiotic resistance genes: Evolution of physiological features and bacterial community. JOURNAL OF HAZARDOUS MATERIALS 2022; 438:129411. [PMID: 35780739 DOI: 10.1016/j.jhazmat.2022.129411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 06/08/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
Supplying conductive materials (CMs) into anaerobic bioreactors is considered as a promising technology for antibiotic wastewater treatment. However, whether and how CMs influence antibiotic resistance genes (ARGs) spread remains poorly known. Here, we investigated the effects of three CMs, i.e., magnetite, activated carbon (AC), and zero valent iron (ZVI), on ARGs dissemination during treating sulfamethoxazole wastewater, by dissecting the shifts of physiological features and microbial community. With the addition of magnetite, AC, and ZVI, the SMX removal was improved from 49.05 to 71.56-92.27 %, while the absolute abundance of ARGs reducing by 26.48 %, 61.95 %, 48.45 %, respectively. The reduced mobile genetic elements and antibiotic resistant bacteria suggested the inhibition of horizontal and vertical transfer of ARGs. The physiological features, including oxidative stress response, quorum sensing, and secretion system may regulate horizontal transfer of ARGs. The addition of all CMs relieved oxidative stress compared with no CMs, but ZVI may cause additional free radicals that needs to be concerned. Further, ZVI and AC also interfered with cell communication and secretion system. This research deepens the insights about the underlying mechanisms of CMs in regulating ARGs, and is expected to propose practical ways for mitigating ARGs proliferation.
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Affiliation(s)
- Qi Zhao
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Wanqian Guo
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China.
| | - Haichao Luo
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Huazhe Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Taiping Yu
- Yangtze Ecology and Environment Co. Ltd., Wuhan 430062, China
| | - Banghai Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Qishi Si
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
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Li J, Ran X, Zhou M, Wang K, Wang H, Wang Y. Oxidative stress and antioxidant mechanisms of obligate anaerobes involved in biological waste treatment processes: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156454. [PMID: 35667421 DOI: 10.1016/j.scitotenv.2022.156454] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/23/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
In-depth understanding of the molecular mechanisms and physiological consequences of oxidative stress is still limited for anaerobes. Anaerobic biotechnology has become widely accepted by the wastewater/sludge industry as a better alternative to more conventional but costly aerobic processes. However, the functional anaerobic microorganisms used in anaerobic biotechnology are frequently hampered by reactive oxygen/nitrogen species (ROS/RNS)-mediated oxidative stress caused by exposure to stressful factors (e.g., oxygen and heavy metals), which negatively impact treatment performance. Thus, identifying stressful factors and understanding antioxidative defense mechanisms of functional obligate anaerobes are crucial for the optimization of anaerobic bioprocesses. Herein, we present a comprehensive overview of oxidative stress and antioxidant mechanisms of obligate anaerobes involved in anaerobic bioprocesses; as examples, we focus on anaerobic ammonium oxidation bacteria and methanogenic archaea. We summarize the primary stress factors in anaerobic bioprocesses and the cellular antioxidant defense systems of functional anaerobes, a consortia of enzymatic and nonenzymatic mechanisms. The dual role of ROS/RNS in cellular processes is elaborated; at low concentrations, they have vital cell signaling functions, but at high concentrations, they cause oxidative damage. Finally, we highlight gaps in knowledge and future work to uncover antioxidant and damage repair mechanisms in obligate anaerobes. This review provides in-depth insights and guidance for future research on oxidative stress of obligate anaerobes to boost the accurate regulation of anaerobic bioprocesses in challenging and changing operating conditions.
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Affiliation(s)
- Jia Li
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Xiaochuan Ran
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Mingda Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Kaichong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China.
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
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Meng Y, Wang D, Wang P, Yu Z, Yuan S, Xia L, Meng F. The counteraction of anammox community to long-term nitrite stress: Crucial roles of rare subcommunity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 822:153062. [PMID: 35031357 DOI: 10.1016/j.scitotenv.2022.153062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/02/2022] [Accepted: 01/07/2022] [Indexed: 06/14/2023]
Abstract
Understanding the temporal dynamics and recovery of anammox community under nitrite stress is critical for successful application of anammox-related processes. Here, the response behaviors of anammox community were investigated to characterize the reactor performance and ecological function under varied levels of nitrite stress (changing from 0, 50, 100, 200 to 0 mg-N/L) across a large temporal scale (588 days). The nitrogen removal rates decreased from 0.51 ± 0.02 to 0.16 ± 0.04 kg-N/(m3·d) under nitrite stress from 0 to 200 mg-N/L, while it was recovered to 0.29 ± 0.06 kg-N/(m3·d) as nitrite stress terminated. A strong community succession was driven by the initial nitrite stress of 50 mg-N/L, while the community dissimilarity mainly resulted from the increased beta diversity of rare subcommunity. Meanwhile, the rare subcommunity with high functional redundancy likely warranted the functional resilience of anammox community across the nitrite stress gradients. Moreover, the increased positive interactions between anammox bacteria and side populations supported the resilience of anammox after discontinuing nitrite stress, which facilitated the recovery of nitrogen removal efficiency. This study deciphers the interspecies interactions and functional redundancy of rare subcommunity in shaping the robustness and resilience of anammox-related processes when treating nitrite fluctuated wastewater.
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Affiliation(s)
- Yabing Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan 410125, PR China
| | - Depeng Wang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan 410125, PR China
| | - Pandeng Wang
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou 510275, PR China
| | - Zhong Yu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan 410125, PR China
| | - Shasha Yuan
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan 410125, PR China
| | - Lichao Xia
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan 410125, PR China
| | - Fangang Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Changsha, Hunan 410125, PR China.
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Shao B, Zhang R, Xu X, Niu L, Fan K, Lin Z, Zhao L, Zhou X, Ren N, Lee DJ, Chen C. Cryptic Sulfur and Oxygen Cycling Potentially Reduces N 2O-Driven Greenhouse Warming: Underlying Revision Need of the Nitrogen Cycle. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:5960-5972. [PMID: 35416037 DOI: 10.1021/acs.est.1c08113] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Increasing global deoxygenation has widely formed oxygen-limited biotopes, altering the metabolic pathways of numerous microbes and causing a large greenhouse effect of nitrous oxide (N2O). Although there are many sources of N2O, denitrification is the sole sink that removes N2O from the biosphere, and the low-level oxygen in waters has been classically thought to be the key factor regulating N2O emissions from incomplete denitrification. However, through microcosm incubations with sandy sediment, we demonstrate here for the first time that the stress from oxygenated environments does not suppress, but rather boosts the complete denitrification process when the sulfur cycle is actively ongoing. This study highlights the potential of reducing N2O-driven greenhouse warming and fills a gap in pre-cognitions on the nitrogen cycle, which may impact our current understanding of greenhouse gas sinks. Combining molecular techniques and kinetic verification, we reveal that dominant inhibitions in oxygen-limited environments can interestingly undergo triple detoxification by cryptic sulfur and oxygen cycling, which may extensively occur in nature but have been long neglected by researchers. Furthermore, reviewing the present data and observations from natural and artificial ecosystems leads to the necessary revision needs of the global nitrogen cycle.
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Affiliation(s)
- Bo Shao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Ruochen Zhang
- School of Civil and Transportation, Hebei University of Technology, Tianjin 300401, China
| | - Xijun Xu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Li Niu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Kaili Fan
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Zhengda Lin
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150090, China
| | - Lei Zhao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xu Zhou
- Engineering Laboratory of Microalgal Bioenergy, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan
| | - Chuan Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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Wang H, Fan Y, Zhou M, Wang W, Li X, Wang Y. Function of Fe(III)-minerals in the enhancement of anammox performance exploiting integrated network and metagenomics analyses. WATER RESEARCH 2022; 210:117998. [PMID: 34968878 DOI: 10.1016/j.watres.2021.117998] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/06/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Iron is a recognized physiological requirement for microorganisms but, for anaerobic ammonium oxidation (anammox) bacteria, its role extends well beyond that of a nutritional necessity. In this study, the function of two typical Fe(III)-minerals (ferrihydrite and magnetite) in anammox processes was evaluated in the absence/presence of Fe(II) by integrated network and metagenomics analyses. Results showed that Fe-(III) minerals addition increased the activity of cellular processes and pathways associated with granule formation, enabling the peak values of particle size to increase by 144% and 115%, respectively. Notably, ferrihydrite (5 mM) enhanced nitrogen removal by 4.8% and 4.1%, respectively, in the short-term and long-term absence of Fe(II). Ferrihydrite also promoted the retention of anammox bacteria affiliated with phylum Planctomycetes in the reactor, contributing to an 11% higher abundance with ferrihydrite amendment when compared with the control (without iron additions) in the short-term absence of Fe(II). Network-based analyses revealed that ferrihydrite facilitated the microbial community to form densely clustered and complex topologies to improve resistance to environmental disturbance (i.e., Fe(II) deficiency), and effectively increased the underlying cooperation and facilitation in the community. Metagenomic analysis revealed that there was limited promotion of anammox central metabolism by the extra addition of Fe(III)-minerals in the presence of Fe(II), highlighting the poor utilization of Fe(III)-minerals by anammox bacteria under Fe(II) sufficiency. This study deepens our understanding of the function of Fe(III)-minerals in anammox systems at the community and functional level, and provides a fundamental basis for developing Fe-based anammox enhancement technologies.
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Affiliation(s)
- Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P R China
| | - Yufei Fan
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P R China
| | - Mingda Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P R China
| | - Weigang Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P R China
| | - Xiang Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P R China.
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Kallistova A, Nikolaev Y, Grachev V, Beletsky A, Gruzdev E, Kadnikov V, Dorofeev A, Berestovskaya J, Pelevina A, Zekker I, Ravin N, Pimenov N, Mardanov A. New Insight Into the Interspecies Shift of Anammox Bacteria Ca. "Brocadia" and Ca. "Jettenia" in Reactors Fed With Formate and Folate. Front Microbiol 2022; 12:802201. [PMID: 35185828 PMCID: PMC8851195 DOI: 10.3389/fmicb.2021.802201] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/02/2021] [Indexed: 12/12/2022] Open
Abstract
The sensitivity of anaerobic ammonium-oxidizing (anammox) bacteria to environmental fluctuations is a frequent cause of reactor malfunctions. It was hypothesized that the addition of formate and folate would have a stimulating effect on anammox bacteria, which in turn would lead to the stability of the anammox process under conditions of a sharp increase in ammonium load, i.e., it helps overcome a stress factor. The effect of formate and folate was investigated using a setup consisting of three parallel sequencing batch reactors equipped with a carrier. Two runs of the reactors were performed. The composition of the microbial community was studied by the 16S rRNA gene profiling and metagenomic analysis. Among anammox bacteria, Ca. "Brocadia" spp. dominated during the first run. A stimulatory effect of folate on the daily nitrogen removal rate (dN) was identified. The addition of formate led to progress in dissimilatory nitrate reduction and stimulated the growth of Ca. "Jettenia" spp. The spatial separation of two anammox species was observed in the formate reactor: Ca. "Brocadia" occupied the carrier and Ca. "Jettenia"-the walls of the reactors. Biomass storage at low temperature without feeding led to an interspecies shift in anammox bacteria in favor of Ca. "Jettenia." During the second run, a domination of Ca. "Jettenia" spp. was recorded along with a stimulating effect of formate, and there was no effect of folate on dN. A comparative genome analysis revealed the patterns suggesting different strategies used by Ca. "Brocadia" and Ca. "Jettenia" spp. to cope with environmental changes.
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Affiliation(s)
- Anna Kallistova
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Yury Nikolaev
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Vladimir Grachev
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexey Beletsky
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Evgeny Gruzdev
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Vitaly Kadnikov
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander Dorofeev
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Julia Berestovskaya
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Anna Pelevina
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Ivar Zekker
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | - Nikolai Ravin
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Nikolai Pimenov
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Andrey Mardanov
- Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
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Wang D, Wang Y, Liu L, Chen Y, Wang C, Li YY, Zhang T. Response and resilience of anammox consortia to nutrient starvation. MICROBIOME 2022; 10:23. [PMID: 35105385 PMCID: PMC8805231 DOI: 10.1186/s40168-021-01212-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 12/09/2021] [Indexed: 05/05/2023]
Abstract
BACKGROUND It is of critical importance to understand how anammox consortia respond to disturbance events and fluctuations in the wastewater treatment reactors. Although the responses of anammox consortia to operational parameters (e.g., temperature, dissolved oxygen, nutrient concentrations) have frequently been reported in previous studies, less is known about their responses and resilience when they suffer from nutrient interruption. RESULTS Here, we investigated the anammox community states and transcriptional patterns before and after a short-term nutrient starvation (3 days) to determine how anammox consortia respond to and recover from such stress. The results demonstrated that the remarkable changes in transcriptional patterns, rather than the community compositions were associated with the nutritional stress. The divergent expression of genes involved in anammox reactions, especially the hydrazine synthase complex (HZS), and nutrient transportation might function as part of a starvation response mechanism in anammox bacteria. In addition, effective energy conservation and substrate supply strategies (ATP accumulation, upregulated amino acid biosynthesis, and enhanced protein degradation) and synergistic interactions between anammox bacteria and heterotrophs might benefit their survival during starvation and the ensuing recovery of the anammox process. Compared with abundant heterotrophs in the anammox system, the overall transcription pattern of the core autotrophic producers (i.e., anammox bacteria) was highly resilient and quickly returned to its pre-starvation state, further contributing to the prompt recovery when the feeding was resumed. CONCLUSIONS These findings provide important insights into nutritional stress-induced changes in transcriptional activities in the anammox consortia and would be beneficial for the understanding of the capacity of anammox consortia in response to stress and process stability in the engineered ecosystems. Video Abstract.
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Affiliation(s)
- Dou Wang
- Environmental Microbiome Engineering and Biotechnology Laboratory, The University of Hong Kong, Hong Kong SAR, China
| | - Yulin Wang
- Environmental Microbiome Engineering and Biotechnology Laboratory, The University of Hong Kong, Hong Kong SAR, China
| | - Lei Liu
- Environmental Microbiome Engineering and Biotechnology Laboratory, The University of Hong Kong, Hong Kong SAR, China
| | - Yiqiang Chen
- Environmental Microbiome Engineering and Biotechnology Laboratory, The University of Hong Kong, Hong Kong SAR, China
| | - Chunxiao Wang
- Environmental Microbiome Engineering and Biotechnology Laboratory, The University of Hong Kong, Hong Kong SAR, China
| | - Yu-You Li
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan
| | - Tong Zhang
- Environmental Microbiome Engineering and Biotechnology Laboratory, The University of Hong Kong, Hong Kong SAR, China
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, China
- Shenzhen Bay Laboratory, Shenzhen, China
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Wang H, Yan Y, Zhang L, Wang Y. Response of antioxidant defense to oxidative stress induced by H 2O 2 and NO in anammox bacteria. CHEMOSPHERE 2021; 282:131008. [PMID: 34082311 DOI: 10.1016/j.chemosphere.2021.131008] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/08/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
Exposure to the stressful environment results in excessive generation of reactive oxygen species (ROS) or reactive nitrogen species (RNS) in anaerobes, which causes deterioration of microbial activities in biological wastewater treatment systems. Although the genes involved in oxidative stress defense have been primarily identified in the genome of Candidatus Kuenenia stuttgartiensis (a typical anammox species), their function is still not verified. Therefore, the expression of putative antioxidation genes kat, sor, and sod in anammox bacteria was studied by in situ transcription and function validated by heterologous expression under the typical ROS (H2O2) and RNS (NO) stress. After H2O2 and NO additions, the genes involved in the anammox central metabolism (nirS, hzsB, and hdh) were immediately down expressed consistent with the decreased anammox activity. However, the expression of putative antioxidation gene kat did not rise when exposed to H2O2; whereas, its encoding protein KAT enhanced the antioxidant actively of anammox bacteria by H2O2 decomposition like the oxidoreductase enzyme catalase. The sod and sor gene were upregulated with NO treatment, and SOD and SOR can combine with NO and decrease its concentration efficiently. These confirmed the important role of kat, sod, and sor as ROS/RNS scavengers in anammox bacteria, with which anammox bacteria protect themselves when they are exposed to the stressful environment. These verified functional enzymes provide directions for the future regulation of anammox systems, which helps to mitigate the inhibitory effect of the stressful environment on anammox bacteria.
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Affiliation(s)
- Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai, 200092, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China
| | - Yuan Yan
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai, 200092, PR China.
| | - Lingmin Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai, 200092, PR China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai, 200092, PR China.
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38
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Anammox-Based Processes for Mature Leachate Treatment in SBR: A Modelling Study. Processes (Basel) 2021. [DOI: 10.3390/pr9081443] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Mature landfill leachates are characterized by high levels of ammoniacal nitrogen which must be reduced for discharge in the sewer system and further treatment in municipal wastewater treatment plants. The use of anammox-based processes can allow for an efficient treatment of ammonium-rich leachates. In this work, two real scale sequencing batch reactors (SBRs), designed to initially perform partial nitritation/anammox (PN/A) and simultaneous partial nitrification and denitrification (SPND) for the treatment of ammonium-rich urban landfill leachate, were modelled using BioWin 6.0 in order to enable plant-wide modelling and optimizing. The constructed models were calibrated and validated using data from long- and short-term (one cycle) SBR operation and fit well to the main physical-chemical parameters (i.e., ammonium, nitrite and nitrate concentrations) measured during short-term (one cycle) operations. Despite the different strategies in terms of dissolved oxygen (DO) concentrations and aeration and mixing patterns applied for SBR operation, the models allowed for understanding that in both reactors the PN/A process was shown as the main contributor to nitrogen removal when the availability of organic carbon was low. Indeed, in both SBRs, the activity of nitrite oxidizing bacteria was inhibited due to high levels of free ammonia, whereas anammox bacteria were active due to the simultaneous presence of ammonium and nitrite and their ability to recover from DO inhibition. Increasing the external carbon addition, a prompt decrease of the anammox biomass was observed, with SPND becoming the main nitrogen removal mechanism. Models were also applied to estimate the production rates of nitrous oxide by aerobic ammonia oxidizing bacteria and heterotrophic denitrifiers. The models were found to be a robust tool for understanding the effects of different operating conditions (i.e, temperature, cycle phases, DO concentration, external carbon addition) on the nitrogen removal performances of the two reactors, assessing the contribution of the different bacterial groups involved.
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